Automatic train-control apparatus



June 26, 1928. 1,675,254

P J. CLIFFORD AUTOMATIC TRAIN CONTROL APPARATUS Original Filed Jan. 5,1923 6' AR. PR 15? TRACK RA IL Inuenivr:

Bai'nick J: CZ gfford,

Patented June 26, 1928.

UNITED STATES UF F' ICE.

PATBIQK J. I cr irronn, QENFALLS, rsivnsYrvAiiia, ass'ieiioa, mt MESNEASSIGN- anrs, T0 'rRArN CONTROL CORPORATION or AMERICA, .A oonromurou orDELA- WARE.

AUTOMATIC TRAIN-coarser. APFARATUS.

Original application filed Jenaary 5, 1922, Serial No. 1928'. SerialThis case is a division of that filed by me January 5, 1923, Serial No.610,880, and concerns a specific form of relay connedhas. Theapplication just mentioned No. 610,880 concerns train control apparatusof the general character disclosedin my application filed April 17,1922, No. 553,429.

In the accompanying drawings Figure 1 is a diagram of one form ofprimary' relay connecton.

F 2 is a view of the relay more in detail.

Inthese drawings 1, 2 are ordinary rails of the trackway, divided iiitoblocks in sulated from each other according to standard practice insignalling systems. The vehicle, which may be considered to be theengihe, of engine and tender combined, or any suitable carrier for theapparatus, is or are of standard fer-in.

The relay PR is in an electric connection, such as 3, the terminals ofwhich are contact with points on the track rails,- and in the foi'insshow'n the contact is made through the wheels and axles of the vehicle,the said relay being adapted to be operated by the current flowingthrough this connection due to the drop in potential between the saidpoints, where the wire is in electrical connection through contacts (theordinary wheels in the example illustrated) on the energized rail.

As an example of means for energizing the trackway rail, I show in Fig.1 a bat-- tery NP and connections leading therefrom to the ends of therail of the block. the insulated joints between which and the adjacentbloclr are shown at l. This relay is polarized, having two contacts 32,79' electrically connected as at 5, the leads being shown at 6, 7 andthe swinging armature at 8 to which the lead 6 is connected. Connection5 will be omitted as noted hereinafter.

One way of electrically connecting the wire 3 with the track rail systemto receive current therefrom is to join the ends of the wire to theupper bearing members or brasses in the journal boxes of the ordinaryaxles of the vehicle, so that these bear ings, the wheel journals andthe Wheels will be in this circuit, though I do not limit myself in thisparticular, it being obvious, however, that it is of material advantageto provide such a connection as will not require alteration of standardequipment, but will 610,880. I Divided and. this application filed May17, No. 278,519.

only entail connection therewith or mountthereon.

As just stated above, the vehicle is of stahdar'd form with ordinaryaxles, and therefore, as set forth in my application Serial Number610,879, no insulation of Wheels, aXles-or other parts of the standardequipmentis employed, and by reason of taking the current through theordinary bearing members or brasses of the journal boxes I avoid the useof collector rings and brushes which by their frictional contact willgen erate current which will unduly affect the primary relay.

The relay PR is responsive to the presence or absence of a prescribedcurrent in the track rail system and it is responsive also to thechanges in polarity of the current received from the track rail system;This prescribed current may be that of the way side signal system or itmay be a current imposcd on the track rail system Where'no Waysidesignal system is employed or it may he that which is imposed on thetrack rail system in addition to that used for operating the signalsystem. In other words, the relay may be calculated to pick up theprescribed current and to remain unaffected by the signal current or bycurrent generated dynamically from the running gear. The change inpolarity of the current through the relay will result from changes inpolarity of the circuit in the track rail system such as may be made tosecure an advance signal indication in the engineers cab, or forresponding to change in the polarity of the track rail system circuitunder other circumstances.

This primary relay may be used to control signals in the cabcorresponding to ordinary wayside block signals, and in addition it maycooperate to control advance caution signal indications, and these cabsignals may be used either with or without the wayside signals. Theprimary relay is also used to control train stop apparatus on the trainand this function may be performed alone or in conjunction with the cabsignals. The primary relay preferably exerts its control upon apparatuscarried by the vehicle through a slow acting relay SAR to take care ofany momentary deenergizing of the primary relay due to crossing theinsulated rail joints or due, for instance, to sand on the track railsystem temporarily interrupting the cir cuit, or to take care of thereversing of the primary relay due to a change in the polarity of thecurrent. The control exerted by the primary relay is continuous, itbeing in electrical connection with the track rail system of the blockconstantly, the track rail system being of standard type with the railselectrically continuous from end to end of the block.

In Fig. l the primary relay PR is in a connection 3 on one side of theVehicle and with points spaced apart along one rail.

In each of the above figures the coil of the relay is shown at c. Therelay may be of the Depre D Arsonval type for direct current withpolarized action of its armature or armatures, and closing on itscontacts on potential say, for instance, above plus or minus 1.5millivolts. The current imposed on the track rail system may be, say, 7amperes, though it will be understood that these figures may be varied.As in my previous application, the energized primary relay, whenenergized by the prescribed current, Will hold the train stop apparatusin condition with the brakes off and upon the absence of said prescribedcurrent the primary relay will assume neutral position, resulting in thebrakes being applied.

In so far as the apparatus on the vehicle is concerned, this may be likethat disclosed in said application, both as regards train stopping meansand also signaling means, and this is true also of the various circuits.

In other words, the subject matter of said application is to be regardedas illustrating how the relay herein may be utilized and his may beregarded as a part of this specification.

Where the range in polarity of the prescribed current is to be utilized,for instance, in getting an advance signal indication the electricalconnection at 5 between the points p 7) will be omitted, see in thisconnection my application No. 610,879 filed Jan. 5, 1923.

It does not appear necessary to illustrate herein all. the mechanismwhich is controlled by the primary relay, it being thought sufiicient toindicate the slow acting relay as representative of any mechanism whichmay be used and which when energized will hold the brakes ofl, and willcause the setting of the brakes in the absence of said prescribedcurrent in the primary relay.

I claim:

The combination of a vehicle track, a trackside circuit including anelectrically continuous portion of one rail of the track, means forsupplying electrical current in either direction in said circuit, and avehicle equipment including a vehicle-carried partial circuit connectedat its terminals to the said rail in parallel with said portion of therail, and a polarized device operable by the flow of current in oppositedirections in said vehicle carried circuit to obtain diiferentcontrolling conditions.

l n testimony whereof, I afiix my signature.

PATRICK J. CLIFFORD.

